1. Field of the Invention
The present invention relates generally to a call processing method and apparatus in a mobile communication system, and in particular, to a call processing method and apparatus for effective control of QoS (Quality of Service) in a mobile communication system.
2. Description of the Related Art
The conventional mobile communication systems that primarily support voice transmission are being replaced by new mobile communication systems that additionally provide packet data services, including high speed packet data service, moving picture transmission, and packetized voice service. These new mobile communication systems aim at providing multimedia services.
However, the new mobile communication systems cannot guarantee rapid and reliable services due to limitations in efficiently and responsively processing traffic, frequent handoffs, call set-up requests from specific mobile stations, and overload. In particular, it is not expected that QoS will be guaranteed through call control and efficient bandwidth management in an IMT-2000 (International Mobile Telecommunication-2000) system with increased packet data services.
For example, a base station in an IMT-2000 system manages resources to guarantee a call service requested by a mobile station within the coverage area of the base station. The IMT-2000 base station establishes the requested call for the mobile station after analyzing the characteristics of the call and carrying on negotiations for frequency assignment with the mobile station. If resources are available, the base station can connect the requested call and guarantee QoS. On the other hand, if resources are not available, the base station rejects the call set-up request even though the call has a higher priority than a current call in progress.
Accordingly, in order to guarantee QoS efficiently, there is need for an apparatus and method in which a base station can accept a call set-up request, even when there exists no available resources, if the requested call has priority over a current call in progress.